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Ultrasound

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Full-Text Articles in Engineering

Towards Patient Specific Mitral Valve Modelling Via Dynamic 3d Transesophageal Echocardiography, Patrick Carnahan Dec 2023

Towards Patient Specific Mitral Valve Modelling Via Dynamic 3d Transesophageal Echocardiography, Patrick Carnahan

Electronic Thesis and Dissertation Repository

Mitral valve disease is a common pathologic problem occurring increasingly in an aging population, and many patients suffering from mitral valve disease require surgical intervention. Planning an interventional approach from diagnostic imaging alone remains a significant clinical challenge. Transesophageal echocardiography (TEE) is the primary imaging modality used diagnostically, it has limitations in image quality and field-of-view. Recently, developments have been made towards modelling patient-specific deformable mitral valves from TEE imaging, however, a major barrier to producing accurate valve models is the need to derive the leaflet geometry through segmentation of diagnostic TEE imaging. This work explores the development of volume …


Detection Of Myofascial Trigger Points With Ultrasound Imaging And Machine Learning, Benjamin Formby Dec 2023

Detection Of Myofascial Trigger Points With Ultrasound Imaging And Machine Learning, Benjamin Formby

All Theses

Myofascial Pain Syndrome (MPS) is a common chronic muscle pain disorder that affects a large portion of the global population, seen in 85-93% of patients in specialty pain clinics [10]. MPS is characterized by hard, palpable nodules caused by a stiffened taut band of muscle fibers. These nodules are referred to as Myofascial Trigger Points (MTrPs) and can be classified by two states: active MTrPs (A-MTrPs) and latent MtrPs (L-MTrPs). Treatment for MPS involves massage therapy, acupuncture, and injections or painkillers. Given the subjectivity of patient pain quantification, MPS can often lead to mistreatment or drug misuse. A deterministic way …


Characterizing Intervertebral Disc Strain Under Dynamic Loading Conditions Using Ultrasound Texture Analysis, Radhika Kulkarni Nov 2023

Characterizing Intervertebral Disc Strain Under Dynamic Loading Conditions Using Ultrasound Texture Analysis, Radhika Kulkarni

Discovery Undergraduate Interdisciplinary Research Internship

Herniated discs in the spine are a significant patient burden, with potential links to lower back and leg discomfort and a considerable impact on daily life. These discs, located between spinal vertebrae, are comprised of the annulus fibrosus (AF) and the nucleus pulposus (NP). Herniations happen when the NP protrudes through a full-thickness annular tear, possibly compressing spinal nerves. The mechanical factors underlying herniated discs are poorly understood, necessitating research into these mechanisms and accessible diagnostic techniques. Our study employs high-resolution ultrasound and texture correlation to quantify strain patterns in intervertebral discs during dynamic loading.

A motion segment from the …


Mitigating Inaudible Ultrasound Attacks On Voice Assistants With Acoustic Metamaterials, Joshua S. Lloyd, Cole G. Ludwikowski, Cyrus Malik, Chen Shen Apr 2023

Mitigating Inaudible Ultrasound Attacks On Voice Assistants With Acoustic Metamaterials, Joshua S. Lloyd, Cole G. Ludwikowski, Cyrus Malik, Chen Shen

Henry M. Rowan College of Engineering Faculty Scholarship

Voice assistants play an important role in facilitating human–machine interactions and have been widely used in audio consumer electronic products. However, it has been shown that they are susceptible to inaudible attacks in which the malicious signals are in the ultrasound regime and cannot be heard by human ears. In this study, we show that a judiciously designed acoustic metamaterial filter can mitigate such attacks by modulating the received signals by the microphones. The metamaterial filter is composed of rigid plates with individual holes which exhibit local resonance phenomena that suppress incoming waves at specific frequencies. The effectiveness of the …


A Device For Measuring Acoustic Output Intensity Of Transcranial Doppler Ultrasound Transducers For Comparison With Fda Regulations, Sarah Altman, Gregory Bashford, Benjamin Hage Apr 2023

A Device For Measuring Acoustic Output Intensity Of Transcranial Doppler Ultrasound Transducers For Comparison With Fda Regulations, Sarah Altman, Gregory Bashford, Benjamin Hage

Honors Theses

Transcranial Doppler Ultrasonography (TCD) is a non-invasive methodology which can evaluate cerebral blood flow velocity in real time. Single-element focused circular transducers placed on the scalp produce ultrasound waves capable of penetrating the skull with minimal aberration, enabling measurement of the Doppler shift. As such, TCD can measure blood flow velocity in the internal carotid and vertebral arteries, as well as the arteries of the Circle of Willis: the Anterior Cerebral (ACA), Posterior Cerebral (PCA), and Middle Cerebral Arteries (MCA). Intracranial aneurysm and ischemic stroke are serious conditions in which ballooning or occlusion of cerebral vessels cause insufficient perfusion, leading …


Using Ultrasonication For The Improvement Of Grade And Recovery In Molybdenum Sulfide Flotation, Wayne Alexander Campbell Dec 2022

Using Ultrasonication For The Improvement Of Grade And Recovery In Molybdenum Sulfide Flotation, Wayne Alexander Campbell

Open Access Theses & Dissertations

Experimentation was performed on molybdenite slurry by using ultrasonication to elucidate the effects of ultrasonic-induced bubble cavitation on the grade, recovery, and gangue reduction during small-scale flotation tests and was followed by a topographical analysis of quartz particles using SEM. Ultrasonic waves at 20-80 kHz that propagate through a liquid medium cause microbubbles to form, grow, and implode. The cavitation bubble's implosion causes brief extreme local conditions where temperatures can reach 5,000 K and pressures of 1,000 bar. The resulting microjets create mechanical and chemical changes to the system and were directed at improving flotation dynamics in these experiments. Through …


Development Of A Near-Full-View Angle Coverage Photoacoustic Tomography System And Its Application Towards Optical Fluence Distribution Imaging, Lawrence Cm Yip Oct 2022

Development Of A Near-Full-View Angle Coverage Photoacoustic Tomography System And Its Application Towards Optical Fluence Distribution Imaging, Lawrence Cm Yip

Electronic Thesis and Dissertation Repository

Photoacoustic tomography (PAT) is a widely explored hybrid imaging modality combining advantages of ultrasound and optical imaging. However, on the acoustic detection side, limited-view angle coverage and limited-detector bandwidth are common key issues in PAT systems that result in unwanted artifacts. While analytical and simulation studies of limited-view artifacts are extensive, experimental setups capable of comparing limited-view to an ideal full-view case are lacking. Due to the lack of PAT systems capable of artifact-free full-view imaging, applications for such a system have also been left unexplored.

A custom ring-shaped detector array was assembled and mounted to a 6-axis robot, which …


Development Of A Hybrid Stereotactic Guidance System For Percutaneous Liver Tumour Ablation, Joeana N. Cambranis Romero Oct 2022

Development Of A Hybrid Stereotactic Guidance System For Percutaneous Liver Tumour Ablation, Joeana N. Cambranis Romero

Electronic Thesis and Dissertation Repository

Stereotactic Image-Guided Surgical Navigation System (IGSNS) supports percutaneous procedures by using medical imaging and tracking information, to assist the surgeons in the preprocedural planning and intraprocedural steps. This thesis describes the development of a stereotactic IGSNS for percutaneous liver tumour ablation, the goal of which is to assist in positioning the tip of the ablation applicator accurately to ensure complete tumour coverage. The main system improvement is the employment of a mini stereotactic patient-attach aiming device that is used as a pointer to ensure needle tip position prior to needle insertion. The thesis chapters describe the development and validation of …


Intracardiac Ultrasound Guided Systems For Transcatheter Cardiac Interventions, Hareem Nisar Aug 2022

Intracardiac Ultrasound Guided Systems For Transcatheter Cardiac Interventions, Hareem Nisar

Electronic Thesis and Dissertation Repository

Transcatheter cardiac interventions are characterized by their percutaneous nature, increased patient safety, and low hospitalization times. Transcatheter procedures involve two major stages: navigation towards the target site and the positioning of tools to deliver the therapy, during which the interventionalists face the challenge of visualizing the anatomy and the relative position of the tools such as a guidewire. Fluoroscopic and transesophageal ultrasound (TEE) imaging are the most used techniques in cardiac procedures; however, they possess the disadvantage of radiation exposure and suboptimal imaging. This work explores the potential of intracardiac ultrasound (ICE) within an image guidance system (IGS) to facilitate …


The External And Internal Geometries Of Rugby Union Players' Shoulder Complex, Angus Hughes, Heather Driscoll, Matt J. Carre Jun 2022

The External And Internal Geometries Of Rugby Union Players' Shoulder Complex, Angus Hughes, Heather Driscoll, Matt J. Carre

International Sports Engineering Association – Engineering of Sport

No abstract provided.


Characterization Of Fundamental Parameters That Modulate Acoustofluidic-Mediated Molecular Delivery To Cells., Connor Sterling Centner May 2022

Characterization Of Fundamental Parameters That Modulate Acoustofluidic-Mediated Molecular Delivery To Cells., Connor Sterling Centner

Electronic Theses and Dissertations

Cell-based therapies represent the latest biotechnological revolution in medicine, but significant limitations exist in non-viral intracellular delivery techniques during manufacturing of cell therapies. To address these limitations, a novel acoustofluidic device was developed to deliver ultrasound waves into a flow chamber for rapid molecular delivery to human cells. Our acoustofluidic device delivers biomolecules by inducing expansion and collapse of exogenous gas-filled microbubbles (“cavitation”), which enhances molecular delivery to nearby cells. Experimental studies were conducted to characterize key parameters that influence acoustofluidic-mediated molecular delivery to human cells. A clinical ultrasound transducer was generally utilized with varying cationic microbubble concentrations. Intracellular delivery …


Multimodal Ultrasound Imaging For Improved Metastatic Lymph Node Detection, Sidhartha Jandhyala Jan 2022

Multimodal Ultrasound Imaging For Improved Metastatic Lymph Node Detection, Sidhartha Jandhyala

Dartmouth College Ph.D Dissertations

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and is complex in nature due to the variety of organs located in the head and neck region. Knowing the metastatic state of the lymph nodes is paramount in accurately staging and treating HNSCC patients. Currently, metastatic lymph node detection involves the use of magnetic resonance imaging and/or x-ray computed tomography, followed by biopsies for histological confirmation. The main diagnostic criteria is the size of the nodes; however, current imaging methods are not 100% accurate due natural lymph node variability. Ultrasound imaging is able to provide …


Photonic Crystal Hydrogels: Simulation, Fabrication & Biomedical Application, Mehenur Sarwar Jan 2022

Photonic Crystal Hydrogels: Simulation, Fabrication & Biomedical Application, Mehenur Sarwar

FIU Electronic Theses and Dissertations

Photonic crystal (PhC) hydrogels are a unique class of material that has tremendous promise as biomedical sensors. The underlying crystal structure allows for simple analysis of microstructural properties by assessing the diffraction pattern generated following laser illumination. The hydrogel medium provides elasticity, regenerability, and potential functionalization. Combining these two properties, photonic crystal hydrogels have the potential for sensing physical forces and chemical reagents using a low-cost, reusable platform.

The development of biomedical sensors using this material is limited due to the lack of a method to accurately predict the diffraction pattern generated. To overcome this, a computational model was developed …


Phase-Changing Nanodroplets As Nanotheranostic Platform For Combination Cancer Therapy, Catalina-Paula Spatarelu Jan 2022

Phase-Changing Nanodroplets As Nanotheranostic Platform For Combination Cancer Therapy, Catalina-Paula Spatarelu

Dartmouth College Ph.D Dissertations

Cancer is a cluster of diseases, and 1.8 million Americans are newly diagnosed each year. Treatment issues such as drug instability, the occurrence of severe side effects, as well as resistance make the need for solutions to improve conventional methods, like chemotherapy, apparent. Nano-sized drug-delivery platforms, particles loaded with therapeutic molecules that escape the immune system clearance and accumulate at the tumor site, were proposed as one of these solutions. Despite the expansion of the field, several aspects still need to be addressed: inconsistent delivery of the drugs, inability of measuring the effective dose being delivered to the tumor, lack …


Characterizing Locomotor Disturbance Perception In Young Adults, Daniel James Liss Jan 2022

Characterizing Locomotor Disturbance Perception In Young Adults, Daniel James Liss

Graduate Theses, Dissertations, and Problem Reports

Falls during walking are a leading cause of injuries across aging. Many of these falls are due to slips and trips. The ability to perceive disturbances to ongoing motion may play an important role in the control of walking balance. However, disturbance perception has been investigated in standing balance, but its role in walking balance due to slip- and trip-like disturbances remains largely unknown. Characterizing locomotor disturbance perception in young adults may lead to a more comprehensive understanding of sensorimotor walking balance control.

This work defined locomotor disturbance perception in response to slip and trip-like disturbances in young adults. We …


Radial Artery Model For Catheterization Procedures, Kyla Beville, Mitchell Gagnon, Benjamin Stalls, Maya Ariza Jan 2022

Radial Artery Model For Catheterization Procedures, Kyla Beville, Mitchell Gagnon, Benjamin Stalls, Maya Ariza

Williams Honors College, Honors Research Projects

The purpose of this project was to create a radial artery model that is usable under ultrasound that would reduce complications during catheterization procedures. Each year, over one million of these procedures are done and complications can affect the outcomes of the patient. Using ultrasound during these procedures is an upcoming way to reduce these complications and improve the outcome that a patient will have.


Characterization Of Effects Of Electric And Acoustic Fields On Fouling During Microfiltration Experiments, Yuxiang Shen Jan 2022

Characterization Of Effects Of Electric And Acoustic Fields On Fouling During Microfiltration Experiments, Yuxiang Shen

Graduate College Dissertations and Theses

Membrane processes have been a promising purification and separation technique as it can potentially remove any ions, particles, and colloids by size selection. Membrane processes are still limitedly used in the real-world industrial application due to its relatively cost prohibitive maintenance and operation, which is attributed to membrane fouling and concentration polarization under pressurized conditions. To improve the efficiency of membrane filtration, alternatives to the traditional cleaning methods have been investigated to mitigate the fouling and concentration polarization problems. Among the alternatives, application of an external field, e.g., electric field or acoustic field, to the mitigate fouling during membrane filtration …


Medical Applications Of Ultrasound: T-Cell Drug Delivery, Osteoporosis Diagnosis, And Biofilm Mitigation, Alina Karki Jan 2022

Medical Applications Of Ultrasound: T-Cell Drug Delivery, Osteoporosis Diagnosis, And Biofilm Mitigation, Alina Karki

Graduate College Dissertations and Theses

The ability of ultrasound to localize acoustic energy deposition and induce a biological effect within a target is examined in three novel biomedical applications: sonoporation, osteoporosis diagnosis, and biofilm mitigation.Ultrasound can excite encapsulated microbubbles, causing an acoustic cavitation effect in the vicinity of cells, temporarily increasing membrane permeability, and allowing cells to uptake foreign molecules. This non-viral transfection technique is called sonoporation. Our experimental study demonstrated that it could be effective for small interfering RNA (siRNA) delivery into an isolated mouse and human T-cells, which is a complex process despite its importance in treating numerous diseases. T-cells are non-proliferating, while …


Photoacoustic Imaging Of Colorectal Cancer And Ovarian Cancer, Xiandong Leng Dec 2021

Photoacoustic Imaging Of Colorectal Cancer And Ovarian Cancer, Xiandong Leng

McKelvey School of Engineering Theses & Dissertations

Photoacoustic (PA) imaging is an emerging hybrid imaging technology that uses a short-pulsed laser to excite tissue. The resulting photoacoustic waves are used to image the optical absorption distribution of the tissue, which is directly related to micro-vessel networks and thus to tumor angiogenesis, a key process in tumor growth and metastasis. In this thesis, the acoustic-resolution photoacoustic microscopy (AR-PAM) was first investigated on its role in human colorectal tissue imaging, and the optical-resolution photoacoustic microscopy (OR-PAM) was investigated on its role in human ovarian tissue imaging.Colorectal cancer is the second leading cause of cancer death in the United States. …


Acoustic Radiation Force And Its Application For Cell Manipulation And Ion Channels Activation, Xiangjun Peng Dec 2021

Acoustic Radiation Force And Its Application For Cell Manipulation And Ion Channels Activation, Xiangjun Peng

McKelvey School of Engineering Theses & Dissertations

Sound is a stress wave that carries energy and momentum flux. Scattered sound waves can generate acoustic radiation force that can be used to manipulate particles or cells. This dissertation demonstrates the physics behind cell manipulation by ultrasound. The work begins with a detailed analysis of the mechanics of using standing surface acoustic waves to fabricate acoustic tweezers for contactless particle manipulation using acoustic radiation force. Models to design and analyze acoustic radiation force have traditionally relied on plane wave theories that cannot predict how standing surface acoustic waves can levitate cells in the direction perpendicular to the substrate. We …


Indoor Positioning Using Synchronized Ultrasonic Ofdma Signals, Julian Bartolone Dec 2021

Indoor Positioning Using Synchronized Ultrasonic Ofdma Signals, Julian Bartolone

Master's Theses

This paper proposes a method of short-range indoor localization using differential phase measurements of synchronized two-tone ultrasonic signals in an Orthogonal Frequency Multiple Access (OFDMA) scheme. This indoor positioning system (IPS) operates at an ultrasonic frequency of approximately 40kHz and synchronizes using an infrared signal. The OFDMA scheme allows for a receiver to process the signals from multiple transmitters continuously without the signals interfering with each other. The phases of the signals are measured using Goertzel Filters, allowing for low-complexity frequency content analysis. A MATLAB simulation using the proposed localization method is performed using four transmitter nodes in the corners …


Ultrasonic Extraction Of Instant Forms Of Plant Substrates In Industrial Production, Shakhnoza Abduvaxitovna Sultanova, Jasur Safarov, Azamat Bakir O'G'Li Usenov, Doston Ishmuhammat Ogli Samandarov, Qobil Akmal Ogli Mukhiddinov Oct 2021

Ultrasonic Extraction Of Instant Forms Of Plant Substrates In Industrial Production, Shakhnoza Abduvaxitovna Sultanova, Jasur Safarov, Azamat Bakir O'G'Li Usenov, Doston Ishmuhammat Ogli Samandarov, Qobil Akmal Ogli Mukhiddinov

Chemical Technology, Control and Management

In recent years, both in our country and abroad, ultrasonic extraction methods have been increasingly used in industrial production, which is associated with the extraction of various substances and compounds from natural plant substrates. Domestic and foreign experience shows that this method has significant advantages over traditional methods and can significantly increase the efficiency and profitability of industrial enterprises, producing complete and functional food products.

This article discusses a brief theory of ultrasonic cavitation and the experience of extracting substrates from plants. Different results have been compared and analyzed.


Mixed-Reality Visualization Environments To Facilitate Ultrasound-Guided Vascular Access, Leah Groves Sep 2021

Mixed-Reality Visualization Environments To Facilitate Ultrasound-Guided Vascular Access, Leah Groves

Electronic Thesis and Dissertation Repository

Ultrasound-guided needle insertions at the site of the internal jugular vein (IJV) are routinely performed to access the central venous system. Ultrasound-guided insertions maintain high rates of carotid artery puncture, as clinicians rely on 2D information to perform a 3D procedure. The limitations of 2D ultrasound-guidance motivated the research question: “Do 3D ultrasound-based environments improve IJV needle insertion accuracy”. We addressed this by developing advanced surgical navigation systems based on tracked surgical tools and ultrasound with various visualizations. The point-to-line ultrasound calibration enables the use of tracked ultrasound. We automated the fiducial localization required for this calibration method such that …


Performance Of Ultrasound-Assisted Forward Osmosis Membrane Process In Desalination Of Seawater, Bara Awwad Al-Sakaji May 2021

Performance Of Ultrasound-Assisted Forward Osmosis Membrane Process In Desalination Of Seawater, Bara Awwad Al-Sakaji

Theses

The objective of this study was to investigate the effect of using ultrasound on water flux through forward osmosis membrane when applied for seawater desalination. A synthetically prepared solution simulating seawater characteristics was used. Parameters considered in the investigation included membrane cross-flow velocity (0.25 and 1.0 cm/s), flow configuration (co-current versus counter-current), direction of ultrasound waves relative to the membrane side (active layer versus support layer), and type of draw solution (NaCl versus MgCl2). Furthermore, a two-level factorial design was considered in the analysis of the results obtained from the experimental work. This study revealed that applying a …


Modeling And Simulation Of Urination Assist System Based On Working Medium Saturated Vapor Pressure, Li Xiao, Li Shu, Weihong Peng, Ting Guan Apr 2021

Modeling And Simulation Of Urination Assist System Based On Working Medium Saturated Vapor Pressure, Li Xiao, Li Shu, Weihong Peng, Ting Guan

Journal of System Simulation

Abstract: To design and analyze the urination assist system driven by ultrasonic-vaporized steam, a simulation model of the driving capsule and three mathematical models of working medium saturated vapor pressure, bladder pressure and urine flow are established. The simulation experiment system is built to verify the model. The effects of radiation time and sound intensity on the working medium temperature and driving pressure are simulated and analyzed. The results show that the working medium temperature and driving pressure are related to the radiation time and sound intensity. Prolonging radiation time and increasing sound intensity can increase the working medium …


Experimental Investigation Of The Effects Of Acoustic Waves On Natural Convection Heat Transfer From A Horizontal Cylinder In Air, Katherina V. Prodanov Mar 2021

Experimental Investigation Of The Effects Of Acoustic Waves On Natural Convection Heat Transfer From A Horizontal Cylinder In Air, Katherina V. Prodanov

Master's Theses

Heat transfer is a critical part of engineering design, from the cooling of rocket engines to the thermal management of the increasingly dense packaging of electronic circuits. Even for the most fundamental modes of heat transfer, a topic of research is devoted to finding novel ways to improve it. In recent decades, investigators experimented with the idea of exposing systems to acoustic waves with the hope of enhancing thermal transfer at the surface of a body. Ultrasound has been applied with some success to systems undergoing nucleate boiling and in single-phase forced and free convection heat transfer in water. However, …


Application Of Ultrasonic Measurements For The Evaluation Of Steel Fiber Reinforced Concrete, Belayhun Gebretsadik, Kazem Jdidirendi, Visar Farhangi, Moses Karakouzian Jan 2021

Application Of Ultrasonic Measurements For The Evaluation Of Steel Fiber Reinforced Concrete, Belayhun Gebretsadik, Kazem Jdidirendi, Visar Farhangi, Moses Karakouzian

Civil and Environmental Engineering and Construction Faculty Research

This study investigates the feasibility of the application of ultrasonic measurement to characterize Steel-Fiber-Reinforced Concrete (SFRC). Specifically, the effects of steel fiber content, age, moisture content, and fiber orientation on Ultrasonic-Pulse-Velocity (UPV) were investigated. In this regard, beam and cylindrical samples were fabricated with different steel fiber contents. The result indicated that for beam specimens the UPV increases with the addition of fiber up to 2% and decreases for higher fiber percentages. Additionally, the fiber orientation within the beam specimens influences the UPV measurements. For cylindrical samples, the rate of UPV decreased with the addition of steel fiber reinforcement. In …


Experimental Analysis Of Ultrasonic Multiple Scattering Attenuation Through The Air With Fine Dust, Ukyong Woo, Hajin Choi, Homin Song Jan 2021

Experimental Analysis Of Ultrasonic Multiple Scattering Attenuation Through The Air With Fine Dust, Ukyong Woo, Hajin Choi, Homin Song

Michigan Tech Publications

In this study, we experimentally evaluated the application of multiple scattering theory for measuring ultrasonic attenuation. Based on the independent approximation theory, the method adopted for calculating the attenuation of coherent waves through air with fine dust is discussed. To obtain a scattering wavefield, a unique ultrasonic scattering hardware was developed, and signal processing schemes were suggested. Four cases of standard particle doses (0, 0.004, 0.008, and 0.012 g) were investigated inside a chamber. The results obtained from the experiments demonstrate that the proposed signal processing approach successfully calculates the scattering attenuation, which correlates well with the applied doses of …


Numerical Analysis Of Ultrasonic Multiple Scattering For Fine Dust Number Density Estimation, Homin Song, Ukyong Woo, Hajin Choi Jan 2021

Numerical Analysis Of Ultrasonic Multiple Scattering For Fine Dust Number Density Estimation, Homin Song, Ukyong Woo, Hajin Choi

Michigan Tech Publications

In this study, a method is presented for estimating the number density of fine dust particles (the number of particles per unit area) through numerical simulations of multiply scattered ultrasonic wavefields. The theoretical background of the multiple scattering of ultrasonic waves under different regimes is introduced. A series of numerical simulations were performed to generate multiply scattered ultrasonic wavefield data. The generated datasets are subsequently processed using an ultrasound data processing approach to estimate the number density of fine dust particles in the air based on the independent scattering approximation theory. The data processing results demonstrate that the proposed approach …


Multiparametric Quantitative Acoustic Imaging Of Cervical Remodeling During Pregnancy, Yan Yan Jan 2021

Multiparametric Quantitative Acoustic Imaging Of Cervical Remodeling During Pregnancy, Yan Yan

Wayne State University Dissertations

The uterine cervix plays a central role in the maintenance of pregnancy and the process of parturition. Untimely cervical ripening in early gestation predisposes to preterm labor and delivery, the leading cause of infant mortality worldwide. The current approach to evaluate the status of the cervix relies on digital and sonographic examination, which indicates the morphological changes of the cervix (cervical length). Therefore, assessing cervix tissue composition changes may provide more sensitive evaluations about cervix status beyond cervical length. Photoacoustic (PA) imaging is a relatively new, non-invasive ultrasound (US) based technology that captures acoustic signals emitted by tissue components in …